Commit 5d1c93ce authored by David Howells's avatar David Howells

Annotate hardware config module parameters in drivers/watchdog/

When the kernel is running in secure boot mode, we lock down the kernel to
prevent userspace from modifying the running kernel image.  Whilst this
includes prohibiting access to things like /dev/mem, it must also prevent
access by means of configuring driver modules in such a way as to cause a
device to access or modify the kernel image.

To this end, annotate module_param* statements that refer to hardware
configuration and indicate for future reference what type of parameter they
specify.  The parameter parser in the core sees this information and can
skip such parameters with an error message if the kernel is locked down.
The module initialisation then runs as normal, but just sees whatever the
default values for those parameters is.

Note that we do still need to do the module initialisation because some
drivers have viable defaults set in case parameters aren't specified and
some drivers support automatic configuration (e.g. PNP or PCI) in addition
to manually coded parameters.

This patch annotates drivers in drivers/watchdog/.
Suggested-by: default avatarAlan Cox <gnomes@lxorguk.ukuu.org.uk>
Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
Reviewed-by: default avatarGuenter Roeck <linux@roeck-us.net>
cc: Wim Van Sebroeck <wim@iguana.be>
cc: Zwane Mwaikambo <zwanem@gmail.com>
cc: linux-watchdog@vger.kernel.org
parent c729203d
...@@ -289,7 +289,7 @@ MODULE_DESCRIPTION("sma cpu5 watchdog driver"); ...@@ -289,7 +289,7 @@ MODULE_DESCRIPTION("sma cpu5 watchdog driver");
MODULE_SUPPORTED_DEVICE("sma cpu5 watchdog"); MODULE_SUPPORTED_DEVICE("sma cpu5 watchdog");
MODULE_LICENSE("GPL"); MODULE_LICENSE("GPL");
module_param(port, int, 0); module_param_hw(port, int, ioport, 0);
MODULE_PARM_DESC(port, "base address of watchdog card, default is 0x91"); MODULE_PARM_DESC(port, "base address of watchdog card, default is 0x91");
module_param(verbose, int, 0); module_param(verbose, int, 0);
......
...@@ -97,9 +97,9 @@ MODULE_PARM_DESC(nowayout, ...@@ -97,9 +97,9 @@ MODULE_PARM_DESC(nowayout,
#define WDT_TIMER_CFG 0xf3 #define WDT_TIMER_CFG 0xf3
module_param(io, int, 0); module_param_hw(io, int, ioport, 0);
MODULE_PARM_DESC(io, "Eurotech WDT io port (default=0x3f0)"); MODULE_PARM_DESC(io, "Eurotech WDT io port (default=0x3f0)");
module_param(irq, int, 0); module_param_hw(irq, int, irq, 0);
MODULE_PARM_DESC(irq, "Eurotech WDT irq (default=10)"); MODULE_PARM_DESC(irq, "Eurotech WDT irq (default=10)");
module_param(ev, charp, 0); module_param(ev, charp, 0);
MODULE_PARM_DESC(ev, "Eurotech WDT event type (default is `int')"); MODULE_PARM_DESC(ev, "Eurotech WDT event type (default is `int')");
......
...@@ -579,7 +579,7 @@ MODULE_AUTHOR("Marcus Junker <junker@anduras.de>"); ...@@ -579,7 +579,7 @@ MODULE_AUTHOR("Marcus Junker <junker@anduras.de>");
MODULE_DESCRIPTION("PC87413 WDT driver"); MODULE_DESCRIPTION("PC87413 WDT driver");
MODULE_LICENSE("GPL"); MODULE_LICENSE("GPL");
module_param(io, int, 0); module_param_hw(io, int, ioport, 0);
MODULE_PARM_DESC(io, MODNAME " I/O port (default: " MODULE_PARM_DESC(io, MODNAME " I/O port (default: "
__MODULE_STRING(IO_DEFAULT) ")."); __MODULE_STRING(IO_DEFAULT) ").");
......
...@@ -88,7 +88,7 @@ MODULE_PARM_DESC(isapnp, ...@@ -88,7 +88,7 @@ MODULE_PARM_DESC(isapnp,
"When set to 0 driver ISA PnP support will be disabled"); "When set to 0 driver ISA PnP support will be disabled");
#endif #endif
module_param(io, int, 0); module_param_hw(io, int, ioport, 0);
MODULE_PARM_DESC(io, "io port"); MODULE_PARM_DESC(io, "io port");
module_param(timeout, int, 0); module_param(timeout, int, 0);
MODULE_PARM_DESC(timeout, "range is 0-255 minutes, default is 1"); MODULE_PARM_DESC(timeout, "range is 0-255 minutes, default is 1");
......
...@@ -78,9 +78,9 @@ static int irq = 11; ...@@ -78,9 +78,9 @@ static int irq = 11;
static DEFINE_SPINLOCK(wdt_lock); static DEFINE_SPINLOCK(wdt_lock);
module_param(io, int, 0); module_param_hw(io, int, ioport, 0);
MODULE_PARM_DESC(io, "WDT io port (default=0x240)"); MODULE_PARM_DESC(io, "WDT io port (default=0x240)");
module_param(irq, int, 0); module_param_hw(irq, int, irq, 0);
MODULE_PARM_DESC(irq, "WDT irq (default=11)"); MODULE_PARM_DESC(irq, "WDT irq (default=11)");
/* Support for the Fan Tachometer on the WDT501-P */ /* Support for the Fan Tachometer on the WDT501-P */
......
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